Piston-type pump



July 23, 1952 H. A. BERLINER PISTON-TYPE PUMP Filed 001;. 6, 1947 INVENTOR. HENRY A. fifRL/NER BY ATTORNEYS Patented July 29, 1952 UNITED STATES PATENT OFFICE PISTON-TYPE PUMP Henry A. Berliner, Washington, D. 0. Application October 6, 1947, Serial No. 778,188

2 Claims.

This invention relates broadly to devices comprising a piston which reciprocates within a cylinder and, while it is useful in all such devices regardless of their use or function, it is of particular utility as applied to pumps and will be described in this application in connection with such a device.

It has been proposed (for example in United States Letters Patent No. 2,313,486 to Gratzmuller and Ignace) to provide a pump or similar device comprising a cylinder, a piston within and of substantially less diameter than the cylinder, and a packing member of elastic material such as rubber disposed within and sealing the annular space between the piston and cylinder and vulcanized or otherwise sealingly attached to both parts. When a force is applied to the piston of such a pump, tending to move it axially of the cylinder, the sealing material is deformed to permit such movement. Thus, the piston may be given a reciprocatory movement, causing deflection of the sealing material in alternately different directions, and providing a pumping action.

I have found that known devices of the described type have only limited utility as they cannot be used for high-pressure pumping purposes. This is due to the fact that the elastic packing or sealing member which fills the annular space between the cylinder and piston is exposed to, and therefore subject to, the full pressure developed within the cylinder, and that this sealing member is necessarily deformed by the pressures developed in high-pressure pumps to such an extent that the member buckles or deforms under the pressure, rendering the pump inoperative.

My invention relates to devices of the described type and has for its principal object the provision of such a device which will not be subject to the described deficiency, whereby such devices may be used for high-pressure pumping.

Other objects and features of novelty of the invention will be made apparent by the following description and the annexed drawings which, it will be understood, are only illustrative of the invention and impose no limitations thereon not imposed by the appended claims.

The single figure of the drawing shows, in sectional view, a high pressure pump constructed in accordance with my invention.

A preferred form of my invention is disclosed in the drawing and comprises a cylinder 2 having a. piston head 4 and piston rod 5 therein. The working face 6 of the piston is spaced from the end wall 8 of the cylinder to provide a pump chamber l0. Exhaust and intake pipes I2, l4 lead through the end wall 8 and contain suitable valves I6, I8 for effecting the required exhaust and intake functions. The end of the cylinder opposite to wall 8 may be open and a cam l9 or other suitable means may be positioned therein in operative engagement with piston rod 5 to effect reciprocation thereof. Elastic sealing ma- 2 terial 26, which may be rubber, fills the space behind the piston head and about the piston rod and is vulcanized, or otherwise bonded, to the inner wall of the cylinder, at 28, and to the outer surface of the piston rod 5, at 30.

In the operation of the disclosed pump the cam I9 is operated to reciprocate the piston through the limited stroke permitted by the yielding of the elastic material 26. Reciprocation of the piston will vary the volume of pump chamber Ill and, in known manner, will draw fluid in through intake pipe [4 and valve I6 and discharge it through pipe l2 and valve 16. The end part 4 0f the piston, which includes the working face 6, is disposed between the elastic sealing material 26 and pump chamber I0 and isolates the sealing material from fluid under pressure in the chamber, thereby permitting any desired high pressure to be built up in the pump chamber without effect on the sealing material.

While I have disclosed one embodiment of my invention, it will be apparent to those skilled in the art that other embodiments, as well as modifications of the one disclosed, may be made without departing in any way from the spirit or scope of the invention, for the limits of which reference must be made to the appended claims.

What is claimed is:

1. A device comprising in combination, a cylinder, a piston within said cylinder having a head of substantially the same diameter as the inner bore of the cylinder, a part of reduced diameter on the opposite side of the head from the working face thereof, and a packing member of elastic material filling the cylinder bore behind the piston head and surrounding the reduced diameter part and bonded to the inner wall of the cylinder and to the outer surface of said reduced diameter part.

2. A device comprising in combination, a cylinder, a piston within said cylinder having a head of substantially the same diameter as the inner bore of the cylinder, a rod attached to said piston on the opposite side of the head from the Working face thereof, and a packing member of resilient material surrounding the rod and substantially filling the cylinder bore behind the piston head and bonded to the inner wall of the cylinder and the outer surface of the piston rod.

HENRY A. BERLINER.

REFERENCES CITED The following references are of record in the 

